The development of dental caries requires the interaction of three elements: a susceptible host, a cariogenic microbial flora and a carbohydrate rich diet [Keyes, P. H., “Recent advances in dental caries research. Bacteriology. Bacteriological findings and biological implications”, International Dental Journal, 1961, Volume 12, page 443; Krasse, B., “Caries Risk. A practical guide for assessment and control”, 1985, Chicago, Quintessence Publishing Company]. This multi-factorial etiology should be taken into account during oral screenings. Indicators such as past caries experience, socioeconomic status, oral hygiene, diet, microbiological factors (lactobacilli, S mutans and yeasts), salivary factors (pH, flow rate, buffer capacity and viscosity) should be incorporated into any screening procedure [Pitts, N. B., “Risk assessment and Caries Prediction”, Journal of Dental Education”, 1998, Volume 62, #10, pages 762-770; Reich, E., Lussi, A., Newbrun, E., “Caries Risk Assessment”, International Dental Journal, 1999, Volume 49, pages 15-26]. Work done by Demers et al. [Demers, M., Brodeur, J-M, Simard, P. L., Mouton, C., Veilleux, G., Frechette, S., “Caries predictors suitable for mass-screenings in children: A literature review”, Community Dental Health, 1990, Volume 7, pages 11-21] concluded that a combination of several factors could provide a more efficient screening test than a single indicator. They felt past caries experience, and microbiological factors stand first because they are easy to determine, they show a reasonably good association with caries and their combination takes into account the three elements that produce caries. The risk assessment can be complemented with more accurate diagnostic methods.
Visual diagnosis of occlusal caries typically has a very low sensitivity and high specificity [ten Cate, J. M., van Amerongen, “Caries Diagnosis, Conventional Methods”, in “Early Detection of Dental Caries, Stookey, G. K., editor, 1996, Indiana University, Indianapolis Ind.]. Sensitivities scatter around a value of 0.3 implying that only 20-48% of the caries present (usually into dentine) are found [Wenzel, A., Larson, M. J., Fejerskov, O, “Detection of occlusal caries without cavitation by visual inspection, film radiographs, xeroradiographs, and digitized radiographs” Caries Research, 1991, Volume 25, pages 365-371; Kidd, E. A. M., Ricketts, Dd. N. J., Pitts, N. B., “Occlusal caries diagnosis: A changing challenge for clinicians and epidemiologists”, J. Dent., 1993, Volume 21, pages 323-331]. For approximal surfaces in vivo, only 22% of the surfaces detected by radiographic methods were detected “clinically” [Hansen, B. F., “Clinical and roentgenologic caries detection”, Dentomaxillofacial Radiology, 1980, Volume 9, pages 34-36]. Angmar-Masson and ten Bosch in 1993 [Angmar-Mansson, B., ten Bosch, J. J., “Advances in methods for diagnosing coronal caries—A review”, Adv. Dent. Res., 1993, Volume 7, #2, pages 70-79] concluded any diagnostic method is preferable to visual examination.
Peers, Mitropoulos and Holloway [1Peers, A., Hill, F. J., Mitropoulos, C. M., Holloway, P. J., “Validity and reproducibility of clinical examination, fibre-optic transillumination and bite-wing radiology for the diagnosis of small approximal carious lesions: An in vitro study”, Caries Research, 1993, Volume 27, pages 307-311] concluded that fibreoptic transillumination and bitewing radiographs are superior to visual examination. These papers studied visual examinations done in a dental office, a much more sophisticated maneuver than an oral screening and still found that visual examination not the ultimate diagnostic tool. Thus visual examinations and for that matter visual screenings may not detect caries that need treatment immediately. A more accurate diagnostic methodology has been reported recently [Jeon R. J., Hellen A., Matvienko A., Mandelis A., Abrams S. H., Amaechi B. T., In vitro Detection and Quantification of Enamel and Root Caries Using Infrared Photothermal Radiometry and Modulated Luminescence. Journal of Biomedical Optics 13(3), 048803, 2008.].
Visual examination, radiographs, measurements or read outs from other diagnostic devices are only indicators or clinical signs that there is disease present or that there has been recent disease. [Featherstone, J. D. B., Young, D. A., et al. “Caries Risk Assessment in Practice for Age 6 through Adult”, CDA Journal 25(10), 703-713, 2007]. These readings and results are a clinical observation that indicates that disease is present. These are not pathological factors but observations. When these observations are combined with the patient's health history and risk factors for developing disease then one can look at the future risk or ongoing risk for disease.
For example, a patient with frank cavities usually has a high level of cariogenic bacteria, and placing restorations does not significantly lower the overall bacterial challenge in the mouth. [Featherstone, J D B., Gansky S A., et al. “A randomized clinical trial of caries management by risk assessment” Caries Research 39(4) 295, 2005]. The evaluation of risk factors combined with more accurate diagnostic methods can assist the oral health care provider with a better means of diagnosis or assessment of the state of dental caries and other diseases of the hard and soft dental tissues, the activity of the disease and chances of the disease continuing or recurring in the future. In oral health care, the combination of these types of data does not exist. Typically devices provide images or output but this is never interpolated into a report.